The Background of Aluminum Foil


Aluminum foil is made from an aluminum alloy which contains between 92 and 99 percent aluminum. Usually between 0.00017 and 0.0059 inches thick, foil is produced in many widths and strengths for literally hundreds of applications. It is used to manufacture thermal insulation for the construction industry, fin stock for air conditioners, electrical coils for transformers, capacitors for radios and televisions, insulation for storage tanks, decorative products, and containers and packaging. The popularity of aluminum foil for so many applications is due to several major advantages, one of the foremost being that the raw materials necessary for its manufacture are plentiful. Aluminum foil is inexpensive, durable, non-toxic, and grease-proof. In addition, it resists chemical attack and provides excellent electrical and non-magnetic shielding.

Aluminum foil's popularity as a packaging material is due to its excellent impermeability to water vapor and gases. It also extends shelf life, uses less storage space, and generates less waste than many other packaging materials. The preference for aluminum in flexible packaging has consequently become a global phenomenon. In Japan, aluminum foil is used as the barrier component in flexible cans. In Europe, aluminum flexible packaging dominates the market for pharmaceutical blister packages and candy wrappers. The aseptic drink box, which uses a thin layer of aluminum foil as a barrier against oxygen, light, and odor, is also quite popular around the world.

Aluminum is the most recently discovered of the metals that modern industry utilizes in large amounts. Known as "alumina," aluminum compounds were used to prepare medicines in ancient Egypt and to set cloth dyes during the Middle Ages. By the early eighteenth century, scientists suspected that these compounds contained a metal, and, in 1807, the English chemist Sir Humphry Davy attempted to isolate it. Although his efforts failed, Davy confirmed that alumina had a metallic base, which he initially called "alumium." Davy later changed this to "aluminum," and, while scientists in many countries spell the term "aluminium," most Americans use Davy's revised spelling.

Then, in 1825, a Danish chemist named Hans Christian Ørsted successfully isolated aluminum, and, twenty years later, a German physicist named Friedrich Wohler was able to create larger particles of the metal, however, Wohler's particles were still only the size of pinheads. In 1854, Henri Sainte-Claire Deville, a French scientist, refined Wohler's method enough to create aluminum lumps as large as marbles. Deville's process provided a foundation for the modern aluminum industry, and the first aluminum bars were displayed in 1855 at the Paris Exposition.